<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=
    , initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <input type="radio" name="gander"> 男
    <input type="radio" name="gander"> 女

<!-- 默认选中 -->
    <input type="radio" name="gander" checked> 女
</body>
</html>